Shadow tables for large tables like Task can hit the static row size limit, resulting in errors during delete recovery and rollback recording operations. It seems that this issue will become more prevalent in London, where shadow tables will experience much heavier use.
Steps to Reproduce
(London) It is unclear how exactly to get a shadow table to have the necessary static row size, but it is achieved over time through numerous rollback recording operations. Once the limit is hit on the sh$task table for example, you can reproduce the error by deleting any task record.
No workaround for this issue is available at this time. Reach out to ServiceNow support if you require assistance with remediating this issue on your instance.
Related Problem: PRB1319549